Hello,

My 300e is using about a quart of oil every 1,000 miles and may be fouling a
plug or two in the process so I'm thinking about replacing the valve stem
seals.  Any advice on what to look out for while doing this job would be
greatly appreciated.  Found the following post on another site and dropped
it in this post for comments on whether it sounds like a valid approach.

Also looking for a good quality valve spring compressor that will work on my
particular engine.  Saw this one on the Snap On site but have no idea
whether it will work.
http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=16398&group_ID=157
5&store=snapon-store&dir=catalog

Read another comment somewhere else which suggested that replacing valve
stem seals was only viable on an older low mileage--implying that in higher
mileage cars the guides tend to leak more oil than the seals.  Any comments
or experience with that?

Thanks,

Mike

---clip---

Hi

Changed the valve stem oil seals on my 190E about 2 years ago or more
although it made little or no difference to oil consumption.
Ayway here goes
Remove HT leads from rocker cover
Remove rocker cover
Remove Spark plugs
Remove oil spray bar
Remove camshaft bearing covers/rockers
The valves are all now visible and the engine can be turned over carefully
with a socket on crank (not cam!!!)until the no. 1 piston is at TDC viewed
through plug hole.
Now this is where it gets scary
Tap the spring of the 2 valves on no. 1 piston with a hammer and drift to
break the seal on the collets.
Use a valve spring compressor to squeeze the spring (the 1 i had was
borrowed it was snap on great tool) and be very careful not to drop the
collrts remove collets and spring .
Valve will fall slightly onto top of piston remove oil seal and replace with
new one lub it before fitting.
Refit vave spring and collets.
Repeat for second valve on no. 1 piston
Turn engine over until no. 2 is at TDC and repeat.
Repeat until all 8 valves are done.
Reassemble using clean oil on bearings etc.

Points to note:
Inlet and Exhaust seals are different.
Do not turn engine over when valve springs are removed.
Tapping the spring to release seal on collets you are using the piston to
restrain the valve be sensible.
Search and get the right tool for the spring compression make one is
possible.
Make sure the piston you are removing the springs on is at TDC if it is not
the valve could fall into the chamber!!!!!!!!
Do not puncture rad with socket on crank bolt.

Good luck

This was over 2 yrs ago

230K